Pediatrics Flashcards
Definitions of neonate, infant, and child
Neonate: Birth to 30 days
Infant: 1 month to 1 year
Child: 1 - 12 years
Kids develop similar physiology to an adult by age
8 years
Premature is considered
< 37 weeks
Fetal transition to neonatal physiology takes place during the first ___-___ hours
24-72
Ductus arteriosus closure
Anatomic closure: 2-6 weeks
High O2 can help it close
Foramen ovale closure
Functionally: rapid closure
Anatomically: 3 months
(until three months deosygenation can cause a reversion back to fetal circualtion worsening the issue)
CV differences in kids
-
Noncompliant LV
- limited ability to handle increase in fluid volume
- Unable to increase SV
-
Heart rate dependent
- only able to increase CO by increasing HR
- (this means that BP depends on HR as well)
-
Limited catecholamine stores
- May give atropine prophylactically - Effect of ephedrine?
-
Fetal circulation considerations
- Cold, hypoxia, and hypercarbia can re-open these shunts
-
Higher metabolic O2 demand than adults
- because they are growing so rapidly!
Pulmonary differences in kids
- Increased O2 consumption (5-9 ml/kg/min)
- TV and dead space same as adults
- dependent on rate for adequate MV for needed O2 demand
- Resp rate is 2-3x that of adults
- Increased chest wall compliance
- Decreased lung compliance**
- SMALL DIAMETER AIRWAYS = increased resistance to flow
- Hypoxia and hypercapnea will depress ventilation
- makes a prommble worse!!!!
- Decreased Type 1 muscle fibers in diaphram
- kid poops out quickly from high RR and poor lung compliance
- Fewer alveoli Smaller FRC****
Unique airway differences in kids
- Narrow nasal passages (lean towards using oral airway)
- Obligate nasal breathing*****
- (until about 6 months, until then, make sure their nose is clear so they can breath!!!)
- Cricoid cartilage is narrowest portion of airway***
- Short neck, large head, large tongue
- Larynx is more cephalad (C4) and is funnel shaped
- Epiglottis is narrow and stubby
- VC attachment is angled anterior and caudad
- Smaller margin of error for R mainstem intubation
How should infants be positioned for intubation?
Slighly neutral and flexed
- Towel roll under shoulders b/c their heads are fucking huge.
- This should align things properly
- Also, neck should be neutral or slightly flexed.
- Extreme flexion or extension will kink airway***
Just 1mm of airway edema can decrease cross-sectional area by ___%
75%
Fluid/Electrolyte differences in kids
- Higher total body water ECF = 40% of TBW in neonates and 20% of TBW in those over 2 years
- More ECF = more prone to dehydration
Kidney function reaches normal by __ months
6 months
Until this time, every week counts for kidney development!!
Peaks at 2 years
Hemoglobin levels in kids
- Hgb pre-term = 13-15 g/dL
- Hgb at birth = 18-20 g/dL
- Most is fetal Hgb = shift to the left! helps extract O2 from mom.
- Low Hgb levels bad in newborn d/t shift to the left.
- Hgb at 2 months = 10-12 g/dL
- Lower threshold for transfusion
- Hgb at 6-24 months = 12 g/dL
- Hgb at 2-6 years = 12.5 g/dL
- Hgb at 6-12 years = 13.5 g/dL
- In newborn blood loss >10-15% may not be tolerated Fetal Hgb
- Most kids though end up doing ok with low hgb.
- Always check with surgeon before giving blood to a kid.
Hepatic and GI differences in kids
- Low hepatic blood flow in first months of life
- CYP450 maturity has huge variability
- Type 1 reactions mature faster than Type 2 (conjugation) = avoid drugs that undergo type 2
- Low glycogen stores (worry about hypoglycemia!)
- glucose in MAINTINENCE fluids
- Impaired conjugation = jaundice
- Poor coordination with breathing and swallowing until 4-5 months (reflux is common!)
- Low plasma albumin levels
Kids can’t shiver until __ months
3 months
Until then, they rely on brown fat metabolism
Keeping kids warm is a huge priority**
Thermoregulation
- Brown fat metabolism = high O2 consumption
- Thin skin
- Low fat content
- Large surface area
- Interventions: Warmed mattress, blankets, warm room, cover the head, humidify inspired gases, bair hugger
General rules about kids and E1/2t of drugs
Infants: Prolonged E1/2t
Children 2-12: Shortened E1/2t
Reaching adulthood: Normal E1/2t
Highes to lowest MAC requirements
- Infant (highest→but have a lower therepeutic index)
- Neonate Child Adult (lowest)
- Preemies tolerate IAs poorly.
- Use minimally or not at all.